During transportation, aircraft engines such as gas turbine engines must be handled carefully in order to avoid shock loading to engine bearings. Shock loading can occur during an impact, a drop or abrupt back and forth movements. When the engine rotor is not rotating and the engine bearings are supporting the weight of the rotor, only a few rolling elements are in contact with the raceways. In some cases, only two or three rolling elements may be in contact with the raceway of a particular bearing. Therefore, due to the relatively small contact area between the rolling elements and the raceway, a shock load while transporting the engine may result in a very high contact pressure between the rolling elements and the raceway which can be beyond the material's elasticity limit.
Consequently, this phenomenon can produce true brinelling defects in the bearing raceway. True brinelling defects are characterised by indentations or material deformations on the raceway which are of the shape of the contact area between the rolling elements and the raceway, and, are spaced according to the rolling element spacing. True brinelling defects in a bearing raceway can lead to vibrations and noisy engines particularly at slower rotational speeds or at run down and can lead to premature failure of the bearing. Conventional ball bearings are typically more prone to true brinelling damage, however this type of damage can also occur in roller bearings or the like.
Accordingly, there is a need to provide a solution through which engine bearing damage caused by shock loading during the transport of gas turbine engines may be prevented or reduced.